1. Field of the Invention
The present invention relates to an information processing apparatus equipped with an actuator which can be driven by a piezo-electric member and above all, means which can slidingly move a medium by the utilization of the vibration of a piezo-electric member. Particularly, the present invention relates to an information processor equipped with means by which a probe and a medium are relatively moved in the in-plane direction on the basis of the principle of an ultrasonic motor. More particularly, the present invention relates to a device which can be used in such an information processor and which can displace a medium precisely.